Environment
3:37 pm
Wed December 1, 2010

Lake Austin Will Drop By Twelve Feet Next Month

Annoying, non-native plants are growing out of control in Lake Austin, and the city is asking the Lower Colorado River Authority to drop lake levels next month to help fend them off. Lake Austin is a stretch of the Colorado River between the Mansfield and Tom Miller dams.

The LCRA says the drawdown will lower lake levels by about twelve feet. It will start on January 3 and last about three weeks. This is nothing new. The LCRA has been doing this since the 1950s to deal with invasive plants.

This time, the weeds mentioned by the LCRA are hydrilla, which can grow more than 20 feet long, and duckweeds, which float on or just beneath the surface of the water.

The LCRA says the drawdown works by exposing the underwater plants to air and killing off stems and leaves through dehydration. The fix is only temporary though, as the plants begin growing back almost as soon as the water levels are raised.

Here's a video from Texas Parks and Wildlife explaining how invasive plants can cause problems in waterways.